16 bit barrel shifter using 16 1 mux and also using case statements

Design a barrel shifter for 16 bit words in VHDL. This barrel shifter is capable of
logical shifting input toward left and right direction. Two different architecture
designs of the same barrel shifter must be implemented and tested with the
testbench you also need to develop. One architecture (e.g., structural) must use a
16-bit multiplexer (MUX). Another one (e.g., behavioral) you may use “case”
statements to complete. You must not use the operators such as “sll” and “srl” for
your design. Each architecture must be in the separate entity.